This reminds me of something really cool I saw a while ago but I can't find for the life of me, it was a bit of JavaScript that ran in the browser and could be used to send a signal to a nearby AM radio! I can't remember quite how it worked, but I tried it and it definitely did after turning off my monitor which apparently pumps out shit-tons of interference into the bottom end of the mediumwave band. I do remember that it was a demonstration of a security vulnerability for supposedly airgapped systems.
The first time I ever saw something like this was a program called Tempest for Eliza, which would generate patterns on a CRT screen that could be captured by an AM radio.
